Adjustable scaffold-support



(No Model.)

J. J. HAMMER. ADJUSTABLE SGAFFOLD SUPPORT.

No. 450,570. Patented Apr. 14,1891.

UNITED STATES JENS J. HAMMER, OF

PATENT OFFICE.

ST. LOUIS, MISSOURI.

ADJUSTABLE SCAFFOLD-SUPPORT.

SPECIFICATION forming part of Letters Patent No. 450,570, dated April 14, 1891.

Application filed October 16, 1890. Serial No. 368,321. (No model.)

To all whom iv may concern.-

Be it known that I, JENs J. HAMMER, of the city of St. Louis, in the State of Missouri, have invented a certain new and useful Improvement in Adjustable Scaffold-Supports, of which the following is a full, clear, and exact description, reference being had to the ac companying drawings, forming part of this specification.

This invention relates to a vertically-adjustable support for scaffolds, the novel features being set forth in the claim.

Figure I is a perspective view of two of the supports. Fig. II is a perspective view of one of the heads; Fig. III, a horizontal section through the lifting mechanism. Fig. IV is a horizontal section through the support below thelifting mechanism.

The base is extended, having a crucial base frame 1. resting on a floor or the ground.

2 is a tubular post or standard ascending from the middle of the base.

3 are braces extending from the base-frame to the standard.

4 is a bar working vertically in the stand ard and having upon its side a cog-rack 5.

6 is a shaft having journal-bearing in the standard and carrying a spur-Wl1eel7,engag- 'ing the cog-rack 5, so that by turning the shaft the bar 4 may be moved vertically.

8 is a hand-crank upon the shaft 6.

9 is a ratchet-Wheel on the shaft, and 10 isa dog adapted to engage the ratchet-wheel and prevent retrograde rotation of the shaft and downward movement of the bar 4-. The power of the hand-crank of the rack-bar 4 may be increased by usual cog-gear in a manner too Well known to need detailed description.

Theraek-bar has a metal head 11, adapted to receive a beam 12, and having upturned right-angled flanges or lips 13 to restrain the beam from side movement.

The bases 1 of the supports are sufficiently extended to give stability to the scaffold upon them,so that no additional stays are required in ordinary cases.

I claim as my invention- I Asupport for scaffolds haviu g an extended crucial base 1, a tubular post 2, braces 3, eX- tending from the base to said post 2, a bar 4, \vorkingin the post and having upon its side a cog-rack 5, a head 11, having upturned rightangied flanges l3,a cog-Wheel mounted upon a hand-crank shaft and engaging the cograck 5, and a ratchet-wheel 9 and dog 10, all substantially as herein set forth.

JENS J. HAMMER.

In presence of SAML. KNIGHT, A. M. EBERSOLE. 

